PHILADELPHIA (CBS) — Dozens of people, many of them veterans of the submarine service, gathered at Penn’s Landing on Monday to remember those who gave their lives below the waves.

They rang a bell and read the names of all 52 submarines lost during World War II, plus a few from afterward for good measure. Standing just ashore from the museum boat, the USS Becuna, and by the monument to the USS Trigger, lost toward the end of the war, the groups Submarine Veterans of World War II, and Subvets told of the unseen impact.

“1.8% of the entire Navy force in World War II were on the boats, on the submarines,” said Joe Bloomer of Belmar, “and they accounted for 55% of the Japanese shipping sunk.”

Bloomer says a lot of that was merchant shipping, which strangled the Japanese war machine.

The submarine ceremony was capped by a cannon salute from the adjacent USS Olympia, from which there was also a wreath laying in honor of the Unknown Soldier, a function living history guide Max Kaiserman says is in the cruiser’s steel.

“She was chosen to take the Unknown Soldier home from France after World War I,” Kaiserman says, “because she was the most famous U.S. Navy vessel in history at the time, other than the Constitution, but they couldn’t sail the Constitution to France and back.”

The USS Olympia, once a flagship, now needs somebody to pick up the tab for its preservation.